/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.dili.dd.flume.plugin.exthdfs;

import org.apache.flume.Context;
import org.apache.flume.Event;

public interface SequenceFileSerializer {

    Class<?> getKeyClass();

    Class<?> getValueClass();

    /**
     * Format the given event into zero, one or more SequenceFile records
     *
     * @param e event
     * @return a list of records corresponding to the given event
     */
    Iterable<Record> serialize(Event e);

    /**
     * Knows how to construct this output formatter.<br/>
     * <b>Note: Implementations MUST provide a public a no-arg constructor.</b>
     */
    public interface Builder {
        public SequenceFileSerializer build(Context context);
    }

    /**
     * A key-value pair making up a record in an HDFS SequenceFile
     */
    public static class Record {
        private final Object key;
        private final Object value;

        public Record(Object key, Object value) {
            this.key = key;
            this.value = value;
        }

        public Object getKey() {
            return key;
        }

        public Object getValue() {
            return value;
        }
    }

}
